一种低膨胀高刚性的炭纤维网络增强聚丙烯复合材料  

A carbon fiber network/polypropylene composite with a low thermal expansion coefficient and high stiffness

作　　者：袁剑民[1] 冯艳荣[1] 吴振军[2] 王彦军[1] 李丝雨[1] 孙萍[1] 

机构地区：[1]湖南大学材料科学与工程学院,湖南长沙410082 [2]湖南大学化学化工学院,湖南长沙410082

出　　处：《新型炭材料》2017年第3期271-276,共6页New Carbon Materials

基　　金：湖南省科技计划项目(2014FJ4018)~~

摘　　要：利用酚醛树脂粘接短切炭纤维,炭化得到全炭型的稳固炭纤维网络增强体(CFNR),真空浸胶后制得一种低膨胀、高刚性的CFNR/聚丙烯(PP)复合材料。利用扫描电镜和热机械分析仪对CFNR/PP复合材料的微观结构和热机械性能进行表征。结果表明,在相同的载荷条件下,常规短切炭纤维(SCF)/PP复合材料的形变是CFNR/PP复合材料的2.3倍。相同温度下,CFNR/PP复合材料、SCF/PP复合材料和PP的储能模量和弯曲模量都依次下降。在30℃和110℃时,CFNR/PP复合材料的弯曲模量分别为SCF/PP复合材料的1.8倍和2.5倍。而且,CFNR/PP复合材料具有较高的热尺寸稳定性,其平均热膨胀系数(30~120℃)是SCF/PP复合材料的1/4。可见,与松散的短切炭纤维网络增强结构相比,CFNR在提高聚合物复合材料的刚性和热尺寸稳定性方面更有效。A carbon fiber network reinforcement （CFNR） was prepared by bonding short carbon fibers with phenol formaldehyderesin followed by carbonization. The CFNR was vacuum-impregnated with molten polypropylene （PP） to produce a CFNR/PP composite with a low thermal expansion coefficient and high stiffness. The microstructure and thermal mechanical properties of the composite were characterized by scanning electron microscopy and thermal mechanical tests. Results show that CFNR is more effec-tive in improving the stiffness and thermal dimensional stability of polymer matrix composites than short carbon fibers. The deforma-tion rate of a conventional short carbon fiber （SCF）/PP composite is 2. 3 times higher than that of the CFN^PP composite under the same load. The decreasing order of the storage and bend moduli is CFNR/PP 〉 SCF/PP 〉PP. The bend moduli of the CFNR/ PP composite at 30 and 110 益 are about 1.8 and 2.5 times that of the SCF/PP composite, respectively. The average thermal ex-pansion coefficient of the CFNR/PP composite between 30 to 120 益 is 25% of that of the SCF/PP composite.

关 键 词：炭纤维网络增强体 热机械性能 刚性 模量 热膨胀系数 

分 类 号：TQ327.3[化学工程—合成树脂塑料工业]